Lens block



FIG. 1 is a perspective view of a lens block showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a back elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and

FIG. 6 is a side elevational view thereof.

The ornamental design for a lens block, as shown. 